   <script>
        var xhr=new XMLHttpRequest();
        xhr.onreadystatechange=function(){
            if (xhr.readyState===XMLHttpRequest.DONE) {
                var data=xhr.responseXML;
                var booklist=data.getElementsByTagName('booklist')[0];
                console.log(booklist.childNodes);
            }
        };
        xhr.open('GET','/test/xmldata');
        xhr.send();
    </script>